Over 8 million Americans have peripheral vascular disease (PAD). Percutaneous transluminal artery (PTA) treatment of severe PAD involves the use of balloons and stents, but delivery of these therapies is often suboptimal due to inaccuracies in angiographic assessment of vessel size or a lack of proper functional vessel assessment. Additional tools aid clinicians in accurately determining vessel size and function, but these are often unused because of the added time, cost, training, and interpretation required. Guidewires are used in every interventional procedure, so the ability of a guidewire to provide not only a stable platform for therapy delivery, but also a diagnostic tool for vessel structure and function would be valuable. We have developed a fully functional 0.035 LumenRECON (LR) guidewire that has the same mechanical properties as a standard Wholey workhorse guidewire, but also uses electrical impedance technology to assess vessel lumen size and stenosis pressure drop. Thus, the guidewire provides a 3-in-1 functionality (i.e. one workhorse guidewire that acts as a platform for therapy delivery, vessel sizing, and stenosis pressure drop assessment). In this Phase I proposal, we will perform a pre-clinical study to validate the functionality of our 0.035 LumenRECON (LR) guidewire as a standard workhorse guidewire for vessel navigation and an accurate diagnostic tool for luminal sizing and pressure drop measurements in large animals. To accomplish the Phase I objectives, the safety, along with accuracy and repeatability of the sizing (specific aim #1) and pressure drop (specific aim #2) measurements will be assessed in domestic swine and measured against current clinically used tools, such as intravascular ultrasound (IVUS), quantitative angiography (QA), and pressure wires. This proposal addresses the significant and growing national epidemic of PAD and addresses an area that is growing, yet often overlooked. Successful completion of the proposed Aims will allow us to translate our research findings into a device that could drastically improve the treatment of PAD.